OBJECTIVE: Assess patients' perspectives on the severity, time course, and relative importance of swallowing deficit before and after (chemo)radiotherapy for head and neck cancer. STUDY DESIGN: Before-and-after cohort study. SETTING: Head and neck cancer UK multidisciplinary clinic. SUBJECTS AND METHODS: A total of 167 patients with a primary cancer, mostly laryngopharyngeal, completed the MD Anderson Dysphagia Index (MDADI) and the University of Washington Quality of Life Questionnaire (UWQOL) before treatment and at 3, 6, and 12 months. Pretreatment swallowing, age, gender, and tumor site and stage were assessed. Statistical methods used were Mann-Whitney, analysis of variance, and logistic regression. RESULTS: There was a sharp deterioration in swallowing on average by 18%, from before treatment to 3 months post treatment (mean difference in MDADI score = 14.5; P < .001). Treatment schedule, pretreatment score, and age accounted for 37% of the variance in 3-month posttreatment MDADI scores. There was then little improvement from 3 to 12 months. Patients treated with only 50-Gy radiotherapy reported significantly less dysphagia at 1 year than patients receiving higher doses or combined chemoradiation (P < .001). Swallowing was the most commonly prioritized of the 12 UWQOL domains both before and after therapy. The MDADI and UWQOL scores were strongly correlated: ρ > 0.69. CONCLUSION: Swallowing is a top priority before and after treatment for the vast majority of patients with head and neck cancer. Swallowing deteriorates significantly posttreatment (P < .001). Treatment intensity, younger age, and lower pretreatment scores predict long-term dysphagia. After chemoradiation, there is little improvement from 3 to 12 months.